面向二次成像混合的可见光隐式通信系统设计

Visible Light Implicit Communication System Design Utilizing Secondary Imaging Mixing Characteristics

为提升可见光隐式成像通信系统的误码性能,提出一种新型的系统设计方案。在有限硬件条件前提下,考虑显示屏与相机链路间二次成像导致的混合帧问题,对其混合特性进行分析和建模;合理设计发送端同步帧和信息帧,并给出相应的解调处理流程;理论分析了接收信噪比,仿真结果表明混合帧问题越严重,相比与传统互补帧方案信噪比增益就越大。在实验室条件下搭建原型系统,在不同的信号嵌入强度、空间分集复用度以及不同的拍摄距离、角度条件下进行测试。测试结果表明,该系统设计能够有效解决二次成像混合帧问题,实现良好的帧同步效果,极大提高系统误码性能。

In order to improve the error performance of visible light implicit imaging communication system, a novel system design scheme is proposed. Under the premise of limited hardware, taking frame mixing problem caused by the secondary imaging in the display-camera link into account, this paper analyzes and models the mixed characteristics. Then the synchronous frames and information frames are designed reasonably and the corresponding demodulation process is given. Furthermore, the received signal-to-noise ratio is analyzed in theory. Simulation result shows that the more serious the frame mixing problem, the greater the SNR gain compared with the traditional complementary frame scheme. The prototype system is built under laboratory conditions. Experiments are executed under different conditions of signal embedding intensity, space diversity and multiplexing, receiving distance and angle. The experimental results show that the proposed system can effectively solve mixed frame problem caused by the secondary imaging, thus achieving good frame synchronization and greatly improving the system error performance.